RFR [9] 8006627: UUID to/from String performance should be improved by reducing object allocations

[Claes Redestad]

Hi,

please review this patch to improve UUID performance, originally 
proposed by Steven Schlansker, rebased to use the allocation-free 
methods added in https://bugs.openjdk.java.net/browse/JDK-8041972

Webrev: http://cr.openjdk.java.net/~redestad/8006627/webrev.0/
Bug: https://bugs.openjdk.java.net/browse/JDK-8006627

Thanks!

/Claes